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1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * compress_core.c - compress offload core
4 *
5 * Copyright (C) 2011 Intel Corporation
6 * Authors: Vinod Koul <vinod.koul@linux.intel.com>
7 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 */
12#define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
13#define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
14
15#include <linux/file.h>
16#include <linux/fs.h>
17#include <linux/list.h>
18#include <linux/math64.h>
19#include <linux/mm.h>
20#include <linux/mutex.h>
21#include <linux/poll.h>
22#include <linux/slab.h>
23#include <linux/sched.h>
24#include <linux/types.h>
25#include <linux/uio.h>
26#include <linux/uaccess.h>
27#include <linux/module.h>
28#include <linux/compat.h>
29#include <sound/core.h>
30#include <sound/initval.h>
31#include <sound/info.h>
32#include <sound/compress_params.h>
33#include <sound/compress_offload.h>
34#include <sound/compress_driver.h>
35
36/* struct snd_compr_codec_caps overflows the ioctl bit size for some
37 * architectures, so we need to disable the relevant ioctls.
38 */
39#if _IOC_SIZEBITS < 14
40#define COMPR_CODEC_CAPS_OVERFLOW
41#endif
42
43/* TODO:
44 * - add substream support for multiple devices in case of
45 * SND_DYNAMIC_MINORS is not used
46 * - Multiple node representation
47 * driver should be able to register multiple nodes
48 */
49
50static DEFINE_MUTEX(device_mutex);
51
52struct snd_compr_file {
53 unsigned long caps;
54 struct snd_compr_stream stream;
55};
56
57static void error_delayed_work(struct work_struct *work);
58
59/*
60 * a note on stream states used:
61 * we use following states in the compressed core
62 * SNDRV_PCM_STATE_OPEN: When stream has been opened.
63 * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
64 * calling SNDRV_COMPRESS_SET_PARAMS. Running streams will come to this
65 * state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
66 * SNDRV_PCM_STATE_PREPARED: When a stream has been written to (for
67 * playback only). User after setting up stream writes the data buffer
68 * before starting the stream.
69 * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
70 * decoding/encoding and rendering/capturing data.
71 * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
72 * by calling SNDRV_COMPRESS_DRAIN.
73 * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
74 * SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
75 * SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
76 */
77static int snd_compr_open(struct inode *inode, struct file *f)
78{
79 struct snd_compr *compr;
80 struct snd_compr_file *data;
81 struct snd_compr_runtime *runtime;
82 enum snd_compr_direction dirn;
83 int maj = imajor(inode);
84 int ret;
85
86 if ((f->f_flags & O_ACCMODE) == O_WRONLY)
87 dirn = SND_COMPRESS_PLAYBACK;
88 else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
89 dirn = SND_COMPRESS_CAPTURE;
90 else
91 return -EINVAL;
92
93 if (maj == snd_major)
94 compr = snd_lookup_minor_data(iminor(inode),
95 SNDRV_DEVICE_TYPE_COMPRESS);
96 else
97 return -EBADFD;
98
99 if (compr == NULL) {
100 pr_err("no device data!!!\n");
101 return -ENODEV;
102 }
103
104 if (dirn != compr->direction) {
105 pr_err("this device doesn't support this direction\n");
106 snd_card_unref(compr->card);
107 return -EINVAL;
108 }
109
110 data = kzalloc(sizeof(*data), GFP_KERNEL);
111 if (!data) {
112 snd_card_unref(compr->card);
113 return -ENOMEM;
114 }
115
116 INIT_DELAYED_WORK(&data->stream.error_work, error_delayed_work);
117
118 data->stream.ops = compr->ops;
119 data->stream.direction = dirn;
120 data->stream.private_data = compr->private_data;
121 data->stream.device = compr;
122 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
123 if (!runtime) {
124 kfree(data);
125 snd_card_unref(compr->card);
126 return -ENOMEM;
127 }
128 runtime->state = SNDRV_PCM_STATE_OPEN;
129 init_waitqueue_head(&runtime->sleep);
130 data->stream.runtime = runtime;
131 f->private_data = (void *)data;
132 mutex_lock(&compr->lock);
133 ret = compr->ops->open(&data->stream);
134 mutex_unlock(&compr->lock);
135 if (ret) {
136 kfree(runtime);
137 kfree(data);
138 }
139 snd_card_unref(compr->card);
140 return ret;
141}
142
143static int snd_compr_free(struct inode *inode, struct file *f)
144{
145 struct snd_compr_file *data = f->private_data;
146 struct snd_compr_runtime *runtime = data->stream.runtime;
147
148 cancel_delayed_work_sync(&data->stream.error_work);
149
150 switch (runtime->state) {
151 case SNDRV_PCM_STATE_RUNNING:
152 case SNDRV_PCM_STATE_DRAINING:
153 case SNDRV_PCM_STATE_PAUSED:
154 data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
155 break;
156 default:
157 break;
158 }
159
160 data->stream.ops->free(&data->stream);
161 if (!data->stream.runtime->dma_buffer_p)
162 kfree(data->stream.runtime->buffer);
163 kfree(data->stream.runtime);
164 kfree(data);
165 return 0;
166}
167
168static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
169 struct snd_compr_tstamp *tstamp)
170{
171 if (!stream->ops->pointer)
172 return -ENOTSUPP;
173 stream->ops->pointer(stream, tstamp);
174 pr_debug("dsp consumed till %d total %d bytes\n",
175 tstamp->byte_offset, tstamp->copied_total);
176 if (stream->direction == SND_COMPRESS_PLAYBACK)
177 stream->runtime->total_bytes_transferred = tstamp->copied_total;
178 else
179 stream->runtime->total_bytes_available = tstamp->copied_total;
180 return 0;
181}
182
183static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
184 struct snd_compr_avail *avail)
185{
186 memset(avail, 0, sizeof(*avail));
187 snd_compr_update_tstamp(stream, &avail->tstamp);
188 /* Still need to return avail even if tstamp can't be filled in */
189
190 if (stream->runtime->total_bytes_available == 0 &&
191 stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
192 stream->direction == SND_COMPRESS_PLAYBACK) {
193 pr_debug("detected init and someone forgot to do a write\n");
194 return stream->runtime->buffer_size;
195 }
196 pr_debug("app wrote %lld, DSP consumed %lld\n",
197 stream->runtime->total_bytes_available,
198 stream->runtime->total_bytes_transferred);
199 if (stream->runtime->total_bytes_available ==
200 stream->runtime->total_bytes_transferred) {
201 if (stream->direction == SND_COMPRESS_PLAYBACK) {
202 pr_debug("both pointers are same, returning full avail\n");
203 return stream->runtime->buffer_size;
204 } else {
205 pr_debug("both pointers are same, returning no avail\n");
206 return 0;
207 }
208 }
209
210 avail->avail = stream->runtime->total_bytes_available -
211 stream->runtime->total_bytes_transferred;
212 if (stream->direction == SND_COMPRESS_PLAYBACK)
213 avail->avail = stream->runtime->buffer_size - avail->avail;
214
215 pr_debug("ret avail as %lld\n", avail->avail);
216 return avail->avail;
217}
218
219static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
220{
221 struct snd_compr_avail avail;
222
223 return snd_compr_calc_avail(stream, &avail);
224}
225
226static int
227snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
228{
229 struct snd_compr_avail ioctl_avail;
230 size_t avail;
231
232 avail = snd_compr_calc_avail(stream, &ioctl_avail);
233 ioctl_avail.avail = avail;
234
235 switch (stream->runtime->state) {
236 case SNDRV_PCM_STATE_OPEN:
237 return -EBADFD;
238 case SNDRV_PCM_STATE_XRUN:
239 return -EPIPE;
240 default:
241 break;
242 }
243
244 if (copy_to_user((__u64 __user *)arg,
245 &ioctl_avail, sizeof(ioctl_avail)))
246 return -EFAULT;
247 return 0;
248}
249
250static int snd_compr_write_data(struct snd_compr_stream *stream,
251 const char __user *buf, size_t count)
252{
253 void *dstn;
254 size_t copy;
255 struct snd_compr_runtime *runtime = stream->runtime;
256 /* 64-bit Modulus */
257 u64 app_pointer = div64_u64(runtime->total_bytes_available,
258 runtime->buffer_size);
259 app_pointer = runtime->total_bytes_available -
260 (app_pointer * runtime->buffer_size);
261
262 dstn = runtime->buffer + app_pointer;
263 pr_debug("copying %ld at %lld\n",
264 (unsigned long)count, app_pointer);
265 if (count < runtime->buffer_size - app_pointer) {
266 if (copy_from_user(dstn, buf, count))
267 return -EFAULT;
268 } else {
269 copy = runtime->buffer_size - app_pointer;
270 if (copy_from_user(dstn, buf, copy))
271 return -EFAULT;
272 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
273 return -EFAULT;
274 }
275 /* if DSP cares, let it know data has been written */
276 if (stream->ops->ack)
277 stream->ops->ack(stream, count);
278 return count;
279}
280
281static ssize_t snd_compr_write(struct file *f, const char __user *buf,
282 size_t count, loff_t *offset)
283{
284 struct snd_compr_file *data = f->private_data;
285 struct snd_compr_stream *stream;
286 size_t avail;
287 int retval;
288
289 if (snd_BUG_ON(!data))
290 return -EFAULT;
291
292 stream = &data->stream;
293 mutex_lock(&stream->device->lock);
294 /* write is allowed when stream is running or has been steup */
295 switch (stream->runtime->state) {
296 case SNDRV_PCM_STATE_SETUP:
297 case SNDRV_PCM_STATE_PREPARED:
298 case SNDRV_PCM_STATE_RUNNING:
299 break;
300 default:
301 mutex_unlock(&stream->device->lock);
302 return -EBADFD;
303 }
304
305 avail = snd_compr_get_avail(stream);
306 pr_debug("avail returned %ld\n", (unsigned long)avail);
307 /* calculate how much we can write to buffer */
308 if (avail > count)
309 avail = count;
310
311 if (stream->ops->copy) {
312 char __user* cbuf = (char __user*)buf;
313 retval = stream->ops->copy(stream, cbuf, avail);
314 } else {
315 retval = snd_compr_write_data(stream, buf, avail);
316 }
317 if (retval > 0)
318 stream->runtime->total_bytes_available += retval;
319
320 /* while initiating the stream, write should be called before START
321 * call, so in setup move state */
322 if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
323 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
324 pr_debug("stream prepared, Houston we are good to go\n");
325 }
326
327 mutex_unlock(&stream->device->lock);
328 return retval;
329}
330
331
332static ssize_t snd_compr_read(struct file *f, char __user *buf,
333 size_t count, loff_t *offset)
334{
335 struct snd_compr_file *data = f->private_data;
336 struct snd_compr_stream *stream;
337 size_t avail;
338 int retval;
339
340 if (snd_BUG_ON(!data))
341 return -EFAULT;
342
343 stream = &data->stream;
344 mutex_lock(&stream->device->lock);
345
346 /* read is allowed when stream is running, paused, draining and setup
347 * (yes setup is state which we transition to after stop, so if user
348 * wants to read data after stop we allow that)
349 */
350 switch (stream->runtime->state) {
351 case SNDRV_PCM_STATE_OPEN:
352 case SNDRV_PCM_STATE_PREPARED:
353 case SNDRV_PCM_STATE_SUSPENDED:
354 case SNDRV_PCM_STATE_DISCONNECTED:
355 retval = -EBADFD;
356 goto out;
357 case SNDRV_PCM_STATE_XRUN:
358 retval = -EPIPE;
359 goto out;
360 }
361
362 avail = snd_compr_get_avail(stream);
363 pr_debug("avail returned %ld\n", (unsigned long)avail);
364 /* calculate how much we can read from buffer */
365 if (avail > count)
366 avail = count;
367
368 if (stream->ops->copy) {
369 retval = stream->ops->copy(stream, buf, avail);
370 } else {
371 retval = -ENXIO;
372 goto out;
373 }
374 if (retval > 0)
375 stream->runtime->total_bytes_transferred += retval;
376
377out:
378 mutex_unlock(&stream->device->lock);
379 return retval;
380}
381
382static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
383{
384 return -ENXIO;
385}
386
387static __poll_t snd_compr_get_poll(struct snd_compr_stream *stream)
388{
389 if (stream->direction == SND_COMPRESS_PLAYBACK)
390 return EPOLLOUT | EPOLLWRNORM;
391 else
392 return EPOLLIN | EPOLLRDNORM;
393}
394
395static __poll_t snd_compr_poll(struct file *f, poll_table *wait)
396{
397 struct snd_compr_file *data = f->private_data;
398 struct snd_compr_stream *stream;
399 size_t avail;
400 __poll_t retval = 0;
401
402 if (snd_BUG_ON(!data))
403 return EPOLLERR;
404
405 stream = &data->stream;
406
407 mutex_lock(&stream->device->lock);
408
409 switch (stream->runtime->state) {
410 case SNDRV_PCM_STATE_OPEN:
411 case SNDRV_PCM_STATE_XRUN:
412 retval = snd_compr_get_poll(stream) | EPOLLERR;
413 goto out;
414 default:
415 break;
416 }
417
418 poll_wait(f, &stream->runtime->sleep, wait);
419
420 avail = snd_compr_get_avail(stream);
421 pr_debug("avail is %ld\n", (unsigned long)avail);
422 /* check if we have at least one fragment to fill */
423 switch (stream->runtime->state) {
424 case SNDRV_PCM_STATE_DRAINING:
425 /* stream has been woken up after drain is complete
426 * draining done so set stream state to stopped
427 */
428 retval = snd_compr_get_poll(stream);
429 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
430 break;
431 case SNDRV_PCM_STATE_RUNNING:
432 case SNDRV_PCM_STATE_PREPARED:
433 case SNDRV_PCM_STATE_PAUSED:
434 if (avail >= stream->runtime->fragment_size)
435 retval = snd_compr_get_poll(stream);
436 break;
437 default:
438 retval = snd_compr_get_poll(stream) | EPOLLERR;
439 break;
440 }
441out:
442 mutex_unlock(&stream->device->lock);
443 return retval;
444}
445
446static int
447snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
448{
449 int retval;
450 struct snd_compr_caps caps;
451
452 if (!stream->ops->get_caps)
453 return -ENXIO;
454
455 memset(&caps, 0, sizeof(caps));
456 retval = stream->ops->get_caps(stream, &caps);
457 if (retval)
458 goto out;
459 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
460 retval = -EFAULT;
461out:
462 return retval;
463}
464
465#ifndef COMPR_CODEC_CAPS_OVERFLOW
466static int
467snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
468{
469 int retval;
470 struct snd_compr_codec_caps *caps;
471
472 if (!stream->ops->get_codec_caps)
473 return -ENXIO;
474
475 caps = kzalloc(sizeof(*caps), GFP_KERNEL);
476 if (!caps)
477 return -ENOMEM;
478
479 retval = stream->ops->get_codec_caps(stream, caps);
480 if (retval)
481 goto out;
482 if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
483 retval = -EFAULT;
484
485out:
486 kfree(caps);
487 return retval;
488}
489#endif /* !COMPR_CODEC_CAPS_OVERFLOW */
490
491/* revisit this with snd_pcm_preallocate_xxx */
492static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
493 struct snd_compr_params *params)
494{
495 unsigned int buffer_size;
496 void *buffer = NULL;
497
498 buffer_size = params->buffer.fragment_size * params->buffer.fragments;
499 if (stream->ops->copy) {
500 buffer = NULL;
501 /* if copy is defined the driver will be required to copy
502 * the data from core
503 */
504 } else {
505 if (stream->runtime->dma_buffer_p) {
506
507 if (buffer_size > stream->runtime->dma_buffer_p->bytes)
508 dev_err(&stream->device->dev,
509 "Not enough DMA buffer");
510 else
511 buffer = stream->runtime->dma_buffer_p->area;
512
513 } else {
514 buffer = kmalloc(buffer_size, GFP_KERNEL);
515 }
516
517 if (!buffer)
518 return -ENOMEM;
519 }
520 stream->runtime->fragment_size = params->buffer.fragment_size;
521 stream->runtime->fragments = params->buffer.fragments;
522 stream->runtime->buffer = buffer;
523 stream->runtime->buffer_size = buffer_size;
524 return 0;
525}
526
527static int snd_compress_check_input(struct snd_compr_params *params)
528{
529 /* first let's check the buffer parameter's */
530 if (params->buffer.fragment_size == 0 ||
531 params->buffer.fragments > U32_MAX / params->buffer.fragment_size ||
532 params->buffer.fragments == 0)
533 return -EINVAL;
534
535 /* now codec parameters */
536 if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
537 return -EINVAL;
538
539 if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
540 return -EINVAL;
541
542 return 0;
543}
544
545static int
546snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
547{
548 struct snd_compr_params *params;
549 int retval;
550
551 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
552 /*
553 * we should allow parameter change only when stream has been
554 * opened not in other cases
555 */
556 params = memdup_user((void __user *)arg, sizeof(*params));
557 if (IS_ERR(params))
558 return PTR_ERR(params);
559
560 retval = snd_compress_check_input(params);
561 if (retval)
562 goto out;
563
564 retval = snd_compr_allocate_buffer(stream, params);
565 if (retval) {
566 retval = -ENOMEM;
567 goto out;
568 }
569
570 retval = stream->ops->set_params(stream, params);
571 if (retval)
572 goto out;
573
574 stream->metadata_set = false;
575 stream->next_track = false;
576
577 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
578 } else {
579 return -EPERM;
580 }
581out:
582 kfree(params);
583 return retval;
584}
585
586static int
587snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
588{
589 struct snd_codec *params;
590 int retval;
591
592 if (!stream->ops->get_params)
593 return -EBADFD;
594
595 params = kzalloc(sizeof(*params), GFP_KERNEL);
596 if (!params)
597 return -ENOMEM;
598 retval = stream->ops->get_params(stream, params);
599 if (retval)
600 goto out;
601 if (copy_to_user((char __user *)arg, params, sizeof(*params)))
602 retval = -EFAULT;
603
604out:
605 kfree(params);
606 return retval;
607}
608
609static int
610snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
611{
612 struct snd_compr_metadata metadata;
613 int retval;
614
615 if (!stream->ops->get_metadata)
616 return -ENXIO;
617
618 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
619 return -EFAULT;
620
621 retval = stream->ops->get_metadata(stream, &metadata);
622 if (retval != 0)
623 return retval;
624
625 if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
626 return -EFAULT;
627
628 return 0;
629}
630
631static int
632snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
633{
634 struct snd_compr_metadata metadata;
635 int retval;
636
637 if (!stream->ops->set_metadata)
638 return -ENXIO;
639 /*
640 * we should allow parameter change only when stream has been
641 * opened not in other cases
642 */
643 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
644 return -EFAULT;
645
646 retval = stream->ops->set_metadata(stream, &metadata);
647 stream->metadata_set = true;
648
649 return retval;
650}
651
652static inline int
653snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
654{
655 struct snd_compr_tstamp tstamp = {0};
656 int ret;
657
658 ret = snd_compr_update_tstamp(stream, &tstamp);
659 if (ret == 0)
660 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
661 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
662 return ret;
663}
664
665static int snd_compr_pause(struct snd_compr_stream *stream)
666{
667 int retval;
668
669 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
670 return -EPERM;
671 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
672 if (!retval)
673 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
674 return retval;
675}
676
677static int snd_compr_resume(struct snd_compr_stream *stream)
678{
679 int retval;
680
681 if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
682 return -EPERM;
683 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
684 if (!retval)
685 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
686 return retval;
687}
688
689static int snd_compr_start(struct snd_compr_stream *stream)
690{
691 int retval;
692
693 switch (stream->runtime->state) {
694 case SNDRV_PCM_STATE_SETUP:
695 if (stream->direction != SND_COMPRESS_CAPTURE)
696 return -EPERM;
697 break;
698 case SNDRV_PCM_STATE_PREPARED:
699 break;
700 default:
701 return -EPERM;
702 }
703
704 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
705 if (!retval)
706 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
707 return retval;
708}
709
710static int snd_compr_stop(struct snd_compr_stream *stream)
711{
712 int retval;
713
714 switch (stream->runtime->state) {
715 case SNDRV_PCM_STATE_OPEN:
716 case SNDRV_PCM_STATE_SETUP:
717 case SNDRV_PCM_STATE_PREPARED:
718 return -EPERM;
719 default:
720 break;
721 }
722
723 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
724 if (!retval) {
725 snd_compr_drain_notify(stream);
726 stream->runtime->total_bytes_available = 0;
727 stream->runtime->total_bytes_transferred = 0;
728 }
729 return retval;
730}
731
732static void error_delayed_work(struct work_struct *work)
733{
734 struct snd_compr_stream *stream;
735
736 stream = container_of(work, struct snd_compr_stream, error_work.work);
737
738 mutex_lock(&stream->device->lock);
739
740 stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
741 wake_up(&stream->runtime->sleep);
742
743 mutex_unlock(&stream->device->lock);
744}
745
746/*
747 * snd_compr_stop_error: Report a fatal error on a stream
748 * @stream: pointer to stream
749 * @state: state to transition the stream to
750 *
751 * Stop the stream and set its state.
752 *
753 * Should be called with compressed device lock held.
754 */
755int snd_compr_stop_error(struct snd_compr_stream *stream,
756 snd_pcm_state_t state)
757{
758 if (stream->runtime->state == state)
759 return 0;
760
761 stream->runtime->state = state;
762
763 pr_debug("Changing state to: %d\n", state);
764
765 queue_delayed_work(system_power_efficient_wq, &stream->error_work, 0);
766
767 return 0;
768}
769EXPORT_SYMBOL_GPL(snd_compr_stop_error);
770
771static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
772{
773 int ret;
774
775 /*
776 * We are called with lock held. So drop the lock while we wait for
777 * drain complete notification from the driver
778 *
779 * It is expected that driver will notify the drain completion and then
780 * stream will be moved to SETUP state, even if draining resulted in an
781 * error. We can trigger next track after this.
782 */
783 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
784 mutex_unlock(&stream->device->lock);
785
786 /* we wait for drain to complete here, drain can return when
787 * interruption occurred, wait returned error or success.
788 * For the first two cases we don't do anything different here and
789 * return after waking up
790 */
791
792 ret = wait_event_interruptible(stream->runtime->sleep,
793 (stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
794 if (ret == -ERESTARTSYS)
795 pr_debug("wait aborted by a signal\n");
796 else if (ret)
797 pr_debug("wait for drain failed with %d\n", ret);
798
799
800 wake_up(&stream->runtime->sleep);
801 mutex_lock(&stream->device->lock);
802
803 return ret;
804}
805
806static int snd_compr_drain(struct snd_compr_stream *stream)
807{
808 int retval;
809
810 switch (stream->runtime->state) {
811 case SNDRV_PCM_STATE_OPEN:
812 case SNDRV_PCM_STATE_SETUP:
813 case SNDRV_PCM_STATE_PREPARED:
814 case SNDRV_PCM_STATE_PAUSED:
815 return -EPERM;
816 case SNDRV_PCM_STATE_XRUN:
817 return -EPIPE;
818 default:
819 break;
820 }
821
822 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
823 if (retval) {
824 pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
825 wake_up(&stream->runtime->sleep);
826 return retval;
827 }
828
829 return snd_compress_wait_for_drain(stream);
830}
831
832static int snd_compr_next_track(struct snd_compr_stream *stream)
833{
834 int retval;
835
836 /* only a running stream can transition to next track */
837 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
838 return -EPERM;
839
840 /* next track doesn't have any meaning for capture streams */
841 if (stream->direction == SND_COMPRESS_CAPTURE)
842 return -EPERM;
843
844 /* you can signal next track if this is intended to be a gapless stream
845 * and current track metadata is set
846 */
847 if (stream->metadata_set == false)
848 return -EPERM;
849
850 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
851 if (retval != 0)
852 return retval;
853 stream->metadata_set = false;
854 stream->next_track = true;
855 return 0;
856}
857
858static int snd_compr_partial_drain(struct snd_compr_stream *stream)
859{
860 int retval;
861
862 switch (stream->runtime->state) {
863 case SNDRV_PCM_STATE_OPEN:
864 case SNDRV_PCM_STATE_SETUP:
865 case SNDRV_PCM_STATE_PREPARED:
866 case SNDRV_PCM_STATE_PAUSED:
867 return -EPERM;
868 case SNDRV_PCM_STATE_XRUN:
869 return -EPIPE;
870 default:
871 break;
872 }
873
874 /* partial drain doesn't have any meaning for capture streams */
875 if (stream->direction == SND_COMPRESS_CAPTURE)
876 return -EPERM;
877
878 /* stream can be drained only when next track has been signalled */
879 if (stream->next_track == false)
880 return -EPERM;
881
882 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
883 if (retval) {
884 pr_debug("Partial drain returned failure\n");
885 wake_up(&stream->runtime->sleep);
886 return retval;
887 }
888
889 stream->next_track = false;
890 return snd_compress_wait_for_drain(stream);
891}
892
893static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
894{
895 struct snd_compr_file *data = f->private_data;
896 struct snd_compr_stream *stream;
897 int retval = -ENOTTY;
898
899 if (snd_BUG_ON(!data))
900 return -EFAULT;
901
902 stream = &data->stream;
903
904 mutex_lock(&stream->device->lock);
905 switch (_IOC_NR(cmd)) {
906 case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
907 retval = put_user(SNDRV_COMPRESS_VERSION,
908 (int __user *)arg) ? -EFAULT : 0;
909 break;
910 case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
911 retval = snd_compr_get_caps(stream, arg);
912 break;
913#ifndef COMPR_CODEC_CAPS_OVERFLOW
914 case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
915 retval = snd_compr_get_codec_caps(stream, arg);
916 break;
917#endif
918 case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
919 retval = snd_compr_set_params(stream, arg);
920 break;
921 case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
922 retval = snd_compr_get_params(stream, arg);
923 break;
924 case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
925 retval = snd_compr_set_metadata(stream, arg);
926 break;
927 case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
928 retval = snd_compr_get_metadata(stream, arg);
929 break;
930 case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
931 retval = snd_compr_tstamp(stream, arg);
932 break;
933 case _IOC_NR(SNDRV_COMPRESS_AVAIL):
934 retval = snd_compr_ioctl_avail(stream, arg);
935 break;
936 case _IOC_NR(SNDRV_COMPRESS_PAUSE):
937 retval = snd_compr_pause(stream);
938 break;
939 case _IOC_NR(SNDRV_COMPRESS_RESUME):
940 retval = snd_compr_resume(stream);
941 break;
942 case _IOC_NR(SNDRV_COMPRESS_START):
943 retval = snd_compr_start(stream);
944 break;
945 case _IOC_NR(SNDRV_COMPRESS_STOP):
946 retval = snd_compr_stop(stream);
947 break;
948 case _IOC_NR(SNDRV_COMPRESS_DRAIN):
949 retval = snd_compr_drain(stream);
950 break;
951 case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
952 retval = snd_compr_partial_drain(stream);
953 break;
954 case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
955 retval = snd_compr_next_track(stream);
956 break;
957
958 }
959 mutex_unlock(&stream->device->lock);
960 return retval;
961}
962
963/* support of 32bit userspace on 64bit platforms */
964#ifdef CONFIG_COMPAT
965static long snd_compr_ioctl_compat(struct file *file, unsigned int cmd,
966 unsigned long arg)
967{
968 return snd_compr_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
969}
970#endif
971
972static const struct file_operations snd_compr_file_ops = {
973 .owner = THIS_MODULE,
974 .open = snd_compr_open,
975 .release = snd_compr_free,
976 .write = snd_compr_write,
977 .read = snd_compr_read,
978 .unlocked_ioctl = snd_compr_ioctl,
979#ifdef CONFIG_COMPAT
980 .compat_ioctl = snd_compr_ioctl_compat,
981#endif
982 .mmap = snd_compr_mmap,
983 .poll = snd_compr_poll,
984};
985
986static int snd_compress_dev_register(struct snd_device *device)
987{
988 int ret = -EINVAL;
989 struct snd_compr *compr;
990
991 if (snd_BUG_ON(!device || !device->device_data))
992 return -EBADFD;
993 compr = device->device_data;
994
995 pr_debug("reg device %s, direction %d\n", compr->name,
996 compr->direction);
997 /* register compressed device */
998 ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS,
999 compr->card, compr->device,
1000 &snd_compr_file_ops, compr, &compr->dev);
1001 if (ret < 0) {
1002 pr_err("snd_register_device failed %d\n", ret);
1003 return ret;
1004 }
1005 return ret;
1006
1007}
1008
1009static int snd_compress_dev_disconnect(struct snd_device *device)
1010{
1011 struct snd_compr *compr;
1012
1013 compr = device->device_data;
1014 snd_unregister_device(&compr->dev);
1015 return 0;
1016}
1017
1018#ifdef CONFIG_SND_VERBOSE_PROCFS
1019static void snd_compress_proc_info_read(struct snd_info_entry *entry,
1020 struct snd_info_buffer *buffer)
1021{
1022 struct snd_compr *compr = (struct snd_compr *)entry->private_data;
1023
1024 snd_iprintf(buffer, "card: %d\n", compr->card->number);
1025 snd_iprintf(buffer, "device: %d\n", compr->device);
1026 snd_iprintf(buffer, "stream: %s\n",
1027 compr->direction == SND_COMPRESS_PLAYBACK
1028 ? "PLAYBACK" : "CAPTURE");
1029 snd_iprintf(buffer, "id: %s\n", compr->id);
1030}
1031
1032static int snd_compress_proc_init(struct snd_compr *compr)
1033{
1034 struct snd_info_entry *entry;
1035 char name[16];
1036
1037 sprintf(name, "compr%i", compr->device);
1038 entry = snd_info_create_card_entry(compr->card, name,
1039 compr->card->proc_root);
1040 if (!entry)
1041 return -ENOMEM;
1042 entry->mode = S_IFDIR | 0555;
1043 compr->proc_root = entry;
1044
1045 entry = snd_info_create_card_entry(compr->card, "info",
1046 compr->proc_root);
1047 if (entry)
1048 snd_info_set_text_ops(entry, compr,
1049 snd_compress_proc_info_read);
1050 compr->proc_info_entry = entry;
1051
1052 return 0;
1053}
1054
1055static void snd_compress_proc_done(struct snd_compr *compr)
1056{
1057 snd_info_free_entry(compr->proc_info_entry);
1058 compr->proc_info_entry = NULL;
1059 snd_info_free_entry(compr->proc_root);
1060 compr->proc_root = NULL;
1061}
1062
1063static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1064{
1065 strlcpy(compr->id, id, sizeof(compr->id));
1066}
1067#else
1068static inline int snd_compress_proc_init(struct snd_compr *compr)
1069{
1070 return 0;
1071}
1072
1073static inline void snd_compress_proc_done(struct snd_compr *compr)
1074{
1075}
1076
1077static inline void snd_compress_set_id(struct snd_compr *compr, const char *id)
1078{
1079}
1080#endif
1081
1082static int snd_compress_dev_free(struct snd_device *device)
1083{
1084 struct snd_compr *compr;
1085
1086 compr = device->device_data;
1087 snd_compress_proc_done(compr);
1088 put_device(&compr->dev);
1089 return 0;
1090}
1091
1092/*
1093 * snd_compress_new: create new compress device
1094 * @card: sound card pointer
1095 * @device: device number
1096 * @dirn: device direction, should be of type enum snd_compr_direction
1097 * @compr: compress device pointer
1098 */
1099int snd_compress_new(struct snd_card *card, int device,
1100 int dirn, const char *id, struct snd_compr *compr)
1101{
1102 static struct snd_device_ops ops = {
1103 .dev_free = snd_compress_dev_free,
1104 .dev_register = snd_compress_dev_register,
1105 .dev_disconnect = snd_compress_dev_disconnect,
1106 };
1107 int ret;
1108
1109 compr->card = card;
1110 compr->device = device;
1111 compr->direction = dirn;
1112
1113 snd_compress_set_id(compr, id);
1114
1115 snd_device_initialize(&compr->dev, card);
1116 dev_set_name(&compr->dev, "comprC%iD%i", card->number, device);
1117
1118 ret = snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
1119 if (ret == 0)
1120 snd_compress_proc_init(compr);
1121
1122 return ret;
1123}
1124EXPORT_SYMBOL_GPL(snd_compress_new);
1125
1126static int snd_compress_add_device(struct snd_compr *device)
1127{
1128 int ret;
1129
1130 if (!device->card)
1131 return -EINVAL;
1132
1133 /* register the card */
1134 ret = snd_card_register(device->card);
1135 if (ret)
1136 goto out;
1137 return 0;
1138
1139out:
1140 pr_err("failed with %d\n", ret);
1141 return ret;
1142
1143}
1144
1145static int snd_compress_remove_device(struct snd_compr *device)
1146{
1147 return snd_card_free(device->card);
1148}
1149
1150/**
1151 * snd_compress_register - register compressed device
1152 *
1153 * @device: compressed device to register
1154 */
1155int snd_compress_register(struct snd_compr *device)
1156{
1157 int retval;
1158
1159 if (device->name == NULL || device->ops == NULL)
1160 return -EINVAL;
1161
1162 pr_debug("Registering compressed device %s\n", device->name);
1163 if (snd_BUG_ON(!device->ops->open))
1164 return -EINVAL;
1165 if (snd_BUG_ON(!device->ops->free))
1166 return -EINVAL;
1167 if (snd_BUG_ON(!device->ops->set_params))
1168 return -EINVAL;
1169 if (snd_BUG_ON(!device->ops->trigger))
1170 return -EINVAL;
1171
1172 mutex_init(&device->lock);
1173
1174 /* register a compressed card */
1175 mutex_lock(&device_mutex);
1176 retval = snd_compress_add_device(device);
1177 mutex_unlock(&device_mutex);
1178 return retval;
1179}
1180EXPORT_SYMBOL_GPL(snd_compress_register);
1181
1182int snd_compress_deregister(struct snd_compr *device)
1183{
1184 pr_debug("Removing compressed device %s\n", device->name);
1185 mutex_lock(&device_mutex);
1186 snd_compress_remove_device(device);
1187 mutex_unlock(&device_mutex);
1188 return 0;
1189}
1190EXPORT_SYMBOL_GPL(snd_compress_deregister);
1191
1192MODULE_DESCRIPTION("ALSA Compressed offload framework");
1193MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
1194MODULE_LICENSE("GPL v2");
1/*
2 * compress_core.c - compress offload core
3 *
4 * Copyright (C) 2011 Intel Corporation
5 * Authors: Vinod Koul <vinod.koul@linux.intel.com>
6 * Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; version 2 of the License.
12 *
13 * This program is distributed in the hope that it will be useful, but
14 * WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * General Public License for more details.
17 *
18 * You should have received a copy of the GNU General Public License along
19 * with this program; if not, write to the Free Software Foundation, Inc.,
20 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
21 *
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
23 *
24 */
25#define FORMAT(fmt) "%s: %d: " fmt, __func__, __LINE__
26#define pr_fmt(fmt) KBUILD_MODNAME ": " FORMAT(fmt)
27
28#include <linux/file.h>
29#include <linux/fs.h>
30#include <linux/list.h>
31#include <linux/math64.h>
32#include <linux/mm.h>
33#include <linux/mutex.h>
34#include <linux/poll.h>
35#include <linux/slab.h>
36#include <linux/sched.h>
37#include <linux/types.h>
38#include <linux/uio.h>
39#include <linux/uaccess.h>
40#include <linux/module.h>
41#include <sound/core.h>
42#include <sound/initval.h>
43#include <sound/compress_params.h>
44#include <sound/compress_offload.h>
45#include <sound/compress_driver.h>
46
47/* TODO:
48 * - add substream support for multiple devices in case of
49 * SND_DYNAMIC_MINORS is not used
50 * - Multiple node representation
51 * driver should be able to register multiple nodes
52 */
53
54static DEFINE_MUTEX(device_mutex);
55
56struct snd_compr_file {
57 unsigned long caps;
58 struct snd_compr_stream stream;
59};
60
61/*
62 * a note on stream states used:
63 * we use follwing states in the compressed core
64 * SNDRV_PCM_STATE_OPEN: When stream has been opened.
65 * SNDRV_PCM_STATE_SETUP: When stream has been initialized. This is done by
66 * calling SNDRV_COMPRESS_SET_PARAMS. running streams will come to this
67 * state at stop by calling SNDRV_COMPRESS_STOP, or at end of drain.
68 * SNDRV_PCM_STATE_RUNNING: When stream has been started and is
69 * decoding/encoding and rendering/capturing data.
70 * SNDRV_PCM_STATE_DRAINING: When stream is draining current data. This is done
71 * by calling SNDRV_COMPRESS_DRAIN.
72 * SNDRV_PCM_STATE_PAUSED: When stream is paused. This is done by calling
73 * SNDRV_COMPRESS_PAUSE. It can be stopped or resumed by calling
74 * SNDRV_COMPRESS_STOP or SNDRV_COMPRESS_RESUME respectively.
75 */
76static int snd_compr_open(struct inode *inode, struct file *f)
77{
78 struct snd_compr *compr;
79 struct snd_compr_file *data;
80 struct snd_compr_runtime *runtime;
81 enum snd_compr_direction dirn;
82 int maj = imajor(inode);
83 int ret;
84
85 if ((f->f_flags & O_ACCMODE) == O_WRONLY)
86 dirn = SND_COMPRESS_PLAYBACK;
87 else if ((f->f_flags & O_ACCMODE) == O_RDONLY)
88 dirn = SND_COMPRESS_CAPTURE;
89 else
90 return -EINVAL;
91
92 if (maj == snd_major)
93 compr = snd_lookup_minor_data(iminor(inode),
94 SNDRV_DEVICE_TYPE_COMPRESS);
95 else
96 return -EBADFD;
97
98 if (compr == NULL) {
99 pr_err("no device data!!!\n");
100 return -ENODEV;
101 }
102
103 if (dirn != compr->direction) {
104 pr_err("this device doesn't support this direction\n");
105 snd_card_unref(compr->card);
106 return -EINVAL;
107 }
108
109 data = kzalloc(sizeof(*data), GFP_KERNEL);
110 if (!data) {
111 snd_card_unref(compr->card);
112 return -ENOMEM;
113 }
114 data->stream.ops = compr->ops;
115 data->stream.direction = dirn;
116 data->stream.private_data = compr->private_data;
117 data->stream.device = compr;
118 runtime = kzalloc(sizeof(*runtime), GFP_KERNEL);
119 if (!runtime) {
120 kfree(data);
121 snd_card_unref(compr->card);
122 return -ENOMEM;
123 }
124 runtime->state = SNDRV_PCM_STATE_OPEN;
125 init_waitqueue_head(&runtime->sleep);
126 data->stream.runtime = runtime;
127 f->private_data = (void *)data;
128 mutex_lock(&compr->lock);
129 ret = compr->ops->open(&data->stream);
130 mutex_unlock(&compr->lock);
131 if (ret) {
132 kfree(runtime);
133 kfree(data);
134 }
135 snd_card_unref(compr->card);
136 return ret;
137}
138
139static int snd_compr_free(struct inode *inode, struct file *f)
140{
141 struct snd_compr_file *data = f->private_data;
142 struct snd_compr_runtime *runtime = data->stream.runtime;
143
144 switch (runtime->state) {
145 case SNDRV_PCM_STATE_RUNNING:
146 case SNDRV_PCM_STATE_DRAINING:
147 case SNDRV_PCM_STATE_PAUSED:
148 data->stream.ops->trigger(&data->stream, SNDRV_PCM_TRIGGER_STOP);
149 break;
150 default:
151 break;
152 }
153
154 data->stream.ops->free(&data->stream);
155 kfree(data->stream.runtime->buffer);
156 kfree(data->stream.runtime);
157 kfree(data);
158 return 0;
159}
160
161static int snd_compr_update_tstamp(struct snd_compr_stream *stream,
162 struct snd_compr_tstamp *tstamp)
163{
164 if (!stream->ops->pointer)
165 return -ENOTSUPP;
166 stream->ops->pointer(stream, tstamp);
167 pr_debug("dsp consumed till %d total %d bytes\n",
168 tstamp->byte_offset, tstamp->copied_total);
169 if (stream->direction == SND_COMPRESS_PLAYBACK)
170 stream->runtime->total_bytes_transferred = tstamp->copied_total;
171 else
172 stream->runtime->total_bytes_available = tstamp->copied_total;
173 return 0;
174}
175
176static size_t snd_compr_calc_avail(struct snd_compr_stream *stream,
177 struct snd_compr_avail *avail)
178{
179 memset(avail, 0, sizeof(*avail));
180 snd_compr_update_tstamp(stream, &avail->tstamp);
181 /* Still need to return avail even if tstamp can't be filled in */
182
183 if (stream->runtime->total_bytes_available == 0 &&
184 stream->runtime->state == SNDRV_PCM_STATE_SETUP &&
185 stream->direction == SND_COMPRESS_PLAYBACK) {
186 pr_debug("detected init and someone forgot to do a write\n");
187 return stream->runtime->buffer_size;
188 }
189 pr_debug("app wrote %lld, DSP consumed %lld\n",
190 stream->runtime->total_bytes_available,
191 stream->runtime->total_bytes_transferred);
192 if (stream->runtime->total_bytes_available ==
193 stream->runtime->total_bytes_transferred) {
194 if (stream->direction == SND_COMPRESS_PLAYBACK) {
195 pr_debug("both pointers are same, returning full avail\n");
196 return stream->runtime->buffer_size;
197 } else {
198 pr_debug("both pointers are same, returning no avail\n");
199 return 0;
200 }
201 }
202
203 avail->avail = stream->runtime->total_bytes_available -
204 stream->runtime->total_bytes_transferred;
205 if (stream->direction == SND_COMPRESS_PLAYBACK)
206 avail->avail = stream->runtime->buffer_size - avail->avail;
207
208 pr_debug("ret avail as %lld\n", avail->avail);
209 return avail->avail;
210}
211
212static inline size_t snd_compr_get_avail(struct snd_compr_stream *stream)
213{
214 struct snd_compr_avail avail;
215
216 return snd_compr_calc_avail(stream, &avail);
217}
218
219static int
220snd_compr_ioctl_avail(struct snd_compr_stream *stream, unsigned long arg)
221{
222 struct snd_compr_avail ioctl_avail;
223 size_t avail;
224
225 avail = snd_compr_calc_avail(stream, &ioctl_avail);
226 ioctl_avail.avail = avail;
227
228 if (copy_to_user((__u64 __user *)arg,
229 &ioctl_avail, sizeof(ioctl_avail)))
230 return -EFAULT;
231 return 0;
232}
233
234static int snd_compr_write_data(struct snd_compr_stream *stream,
235 const char __user *buf, size_t count)
236{
237 void *dstn;
238 size_t copy;
239 struct snd_compr_runtime *runtime = stream->runtime;
240 /* 64-bit Modulus */
241 u64 app_pointer = div64_u64(runtime->total_bytes_available,
242 runtime->buffer_size);
243 app_pointer = runtime->total_bytes_available -
244 (app_pointer * runtime->buffer_size);
245
246 dstn = runtime->buffer + app_pointer;
247 pr_debug("copying %ld at %lld\n",
248 (unsigned long)count, app_pointer);
249 if (count < runtime->buffer_size - app_pointer) {
250 if (copy_from_user(dstn, buf, count))
251 return -EFAULT;
252 } else {
253 copy = runtime->buffer_size - app_pointer;
254 if (copy_from_user(dstn, buf, copy))
255 return -EFAULT;
256 if (copy_from_user(runtime->buffer, buf + copy, count - copy))
257 return -EFAULT;
258 }
259 /* if DSP cares, let it know data has been written */
260 if (stream->ops->ack)
261 stream->ops->ack(stream, count);
262 return count;
263}
264
265static ssize_t snd_compr_write(struct file *f, const char __user *buf,
266 size_t count, loff_t *offset)
267{
268 struct snd_compr_file *data = f->private_data;
269 struct snd_compr_stream *stream;
270 size_t avail;
271 int retval;
272
273 if (snd_BUG_ON(!data))
274 return -EFAULT;
275
276 stream = &data->stream;
277 mutex_lock(&stream->device->lock);
278 /* write is allowed when stream is running or has been steup */
279 if (stream->runtime->state != SNDRV_PCM_STATE_SETUP &&
280 stream->runtime->state != SNDRV_PCM_STATE_RUNNING) {
281 mutex_unlock(&stream->device->lock);
282 return -EBADFD;
283 }
284
285 avail = snd_compr_get_avail(stream);
286 pr_debug("avail returned %ld\n", (unsigned long)avail);
287 /* calculate how much we can write to buffer */
288 if (avail > count)
289 avail = count;
290
291 if (stream->ops->copy) {
292 char __user* cbuf = (char __user*)buf;
293 retval = stream->ops->copy(stream, cbuf, avail);
294 } else {
295 retval = snd_compr_write_data(stream, buf, avail);
296 }
297 if (retval > 0)
298 stream->runtime->total_bytes_available += retval;
299
300 /* while initiating the stream, write should be called before START
301 * call, so in setup move state */
302 if (stream->runtime->state == SNDRV_PCM_STATE_SETUP) {
303 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
304 pr_debug("stream prepared, Houston we are good to go\n");
305 }
306
307 mutex_unlock(&stream->device->lock);
308 return retval;
309}
310
311
312static ssize_t snd_compr_read(struct file *f, char __user *buf,
313 size_t count, loff_t *offset)
314{
315 struct snd_compr_file *data = f->private_data;
316 struct snd_compr_stream *stream;
317 size_t avail;
318 int retval;
319
320 if (snd_BUG_ON(!data))
321 return -EFAULT;
322
323 stream = &data->stream;
324 mutex_lock(&stream->device->lock);
325
326 /* read is allowed when stream is running, paused, draining and setup
327 * (yes setup is state which we transition to after stop, so if user
328 * wants to read data after stop we allow that)
329 */
330 switch (stream->runtime->state) {
331 case SNDRV_PCM_STATE_OPEN:
332 case SNDRV_PCM_STATE_PREPARED:
333 case SNDRV_PCM_STATE_XRUN:
334 case SNDRV_PCM_STATE_SUSPENDED:
335 case SNDRV_PCM_STATE_DISCONNECTED:
336 retval = -EBADFD;
337 goto out;
338 }
339
340 avail = snd_compr_get_avail(stream);
341 pr_debug("avail returned %ld\n", (unsigned long)avail);
342 /* calculate how much we can read from buffer */
343 if (avail > count)
344 avail = count;
345
346 if (stream->ops->copy) {
347 retval = stream->ops->copy(stream, buf, avail);
348 } else {
349 retval = -ENXIO;
350 goto out;
351 }
352 if (retval > 0)
353 stream->runtime->total_bytes_transferred += retval;
354
355out:
356 mutex_unlock(&stream->device->lock);
357 return retval;
358}
359
360static int snd_compr_mmap(struct file *f, struct vm_area_struct *vma)
361{
362 return -ENXIO;
363}
364
365static inline int snd_compr_get_poll(struct snd_compr_stream *stream)
366{
367 if (stream->direction == SND_COMPRESS_PLAYBACK)
368 return POLLOUT | POLLWRNORM;
369 else
370 return POLLIN | POLLRDNORM;
371}
372
373static unsigned int snd_compr_poll(struct file *f, poll_table *wait)
374{
375 struct snd_compr_file *data = f->private_data;
376 struct snd_compr_stream *stream;
377 size_t avail;
378 int retval = 0;
379
380 if (snd_BUG_ON(!data))
381 return -EFAULT;
382 stream = &data->stream;
383 if (snd_BUG_ON(!stream))
384 return -EFAULT;
385
386 mutex_lock(&stream->device->lock);
387 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
388 retval = -EBADFD;
389 goto out;
390 }
391 poll_wait(f, &stream->runtime->sleep, wait);
392
393 avail = snd_compr_get_avail(stream);
394 pr_debug("avail is %ld\n", (unsigned long)avail);
395 /* check if we have at least one fragment to fill */
396 switch (stream->runtime->state) {
397 case SNDRV_PCM_STATE_DRAINING:
398 /* stream has been woken up after drain is complete
399 * draining done so set stream state to stopped
400 */
401 retval = snd_compr_get_poll(stream);
402 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
403 break;
404 case SNDRV_PCM_STATE_RUNNING:
405 case SNDRV_PCM_STATE_PREPARED:
406 case SNDRV_PCM_STATE_PAUSED:
407 if (avail >= stream->runtime->fragment_size)
408 retval = snd_compr_get_poll(stream);
409 break;
410 default:
411 if (stream->direction == SND_COMPRESS_PLAYBACK)
412 retval = POLLOUT | POLLWRNORM | POLLERR;
413 else
414 retval = POLLIN | POLLRDNORM | POLLERR;
415 break;
416 }
417out:
418 mutex_unlock(&stream->device->lock);
419 return retval;
420}
421
422static int
423snd_compr_get_caps(struct snd_compr_stream *stream, unsigned long arg)
424{
425 int retval;
426 struct snd_compr_caps caps;
427
428 if (!stream->ops->get_caps)
429 return -ENXIO;
430
431 memset(&caps, 0, sizeof(caps));
432 retval = stream->ops->get_caps(stream, &caps);
433 if (retval)
434 goto out;
435 if (copy_to_user((void __user *)arg, &caps, sizeof(caps)))
436 retval = -EFAULT;
437out:
438 return retval;
439}
440
441static int
442snd_compr_get_codec_caps(struct snd_compr_stream *stream, unsigned long arg)
443{
444 int retval;
445 struct snd_compr_codec_caps *caps;
446
447 if (!stream->ops->get_codec_caps)
448 return -ENXIO;
449
450 caps = kzalloc(sizeof(*caps), GFP_KERNEL);
451 if (!caps)
452 return -ENOMEM;
453
454 retval = stream->ops->get_codec_caps(stream, caps);
455 if (retval)
456 goto out;
457 if (copy_to_user((void __user *)arg, caps, sizeof(*caps)))
458 retval = -EFAULT;
459
460out:
461 kfree(caps);
462 return retval;
463}
464
465/* revisit this with snd_pcm_preallocate_xxx */
466static int snd_compr_allocate_buffer(struct snd_compr_stream *stream,
467 struct snd_compr_params *params)
468{
469 unsigned int buffer_size;
470 void *buffer;
471
472 buffer_size = params->buffer.fragment_size * params->buffer.fragments;
473 if (stream->ops->copy) {
474 buffer = NULL;
475 /* if copy is defined the driver will be required to copy
476 * the data from core
477 */
478 } else {
479 buffer = kmalloc(buffer_size, GFP_KERNEL);
480 if (!buffer)
481 return -ENOMEM;
482 }
483 stream->runtime->fragment_size = params->buffer.fragment_size;
484 stream->runtime->fragments = params->buffer.fragments;
485 stream->runtime->buffer = buffer;
486 stream->runtime->buffer_size = buffer_size;
487 return 0;
488}
489
490static int snd_compress_check_input(struct snd_compr_params *params)
491{
492 /* first let's check the buffer parameter's */
493 if (params->buffer.fragment_size == 0 ||
494 params->buffer.fragments > SIZE_MAX / params->buffer.fragment_size)
495 return -EINVAL;
496
497 /* now codec parameters */
498 if (params->codec.id == 0 || params->codec.id > SND_AUDIOCODEC_MAX)
499 return -EINVAL;
500
501 if (params->codec.ch_in == 0 || params->codec.ch_out == 0)
502 return -EINVAL;
503
504 return 0;
505}
506
507static int
508snd_compr_set_params(struct snd_compr_stream *stream, unsigned long arg)
509{
510 struct snd_compr_params *params;
511 int retval;
512
513 if (stream->runtime->state == SNDRV_PCM_STATE_OPEN) {
514 /*
515 * we should allow parameter change only when stream has been
516 * opened not in other cases
517 */
518 params = kmalloc(sizeof(*params), GFP_KERNEL);
519 if (!params)
520 return -ENOMEM;
521 if (copy_from_user(params, (void __user *)arg, sizeof(*params))) {
522 retval = -EFAULT;
523 goto out;
524 }
525
526 retval = snd_compress_check_input(params);
527 if (retval)
528 goto out;
529
530 retval = snd_compr_allocate_buffer(stream, params);
531 if (retval) {
532 retval = -ENOMEM;
533 goto out;
534 }
535
536 retval = stream->ops->set_params(stream, params);
537 if (retval)
538 goto out;
539
540 stream->metadata_set = false;
541 stream->next_track = false;
542
543 if (stream->direction == SND_COMPRESS_PLAYBACK)
544 stream->runtime->state = SNDRV_PCM_STATE_SETUP;
545 else
546 stream->runtime->state = SNDRV_PCM_STATE_PREPARED;
547 } else {
548 return -EPERM;
549 }
550out:
551 kfree(params);
552 return retval;
553}
554
555static int
556snd_compr_get_params(struct snd_compr_stream *stream, unsigned long arg)
557{
558 struct snd_codec *params;
559 int retval;
560
561 if (!stream->ops->get_params)
562 return -EBADFD;
563
564 params = kzalloc(sizeof(*params), GFP_KERNEL);
565 if (!params)
566 return -ENOMEM;
567 retval = stream->ops->get_params(stream, params);
568 if (retval)
569 goto out;
570 if (copy_to_user((char __user *)arg, params, sizeof(*params)))
571 retval = -EFAULT;
572
573out:
574 kfree(params);
575 return retval;
576}
577
578static int
579snd_compr_get_metadata(struct snd_compr_stream *stream, unsigned long arg)
580{
581 struct snd_compr_metadata metadata;
582 int retval;
583
584 if (!stream->ops->get_metadata)
585 return -ENXIO;
586
587 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
588 return -EFAULT;
589
590 retval = stream->ops->get_metadata(stream, &metadata);
591 if (retval != 0)
592 return retval;
593
594 if (copy_to_user((void __user *)arg, &metadata, sizeof(metadata)))
595 return -EFAULT;
596
597 return 0;
598}
599
600static int
601snd_compr_set_metadata(struct snd_compr_stream *stream, unsigned long arg)
602{
603 struct snd_compr_metadata metadata;
604 int retval;
605
606 if (!stream->ops->set_metadata)
607 return -ENXIO;
608 /*
609 * we should allow parameter change only when stream has been
610 * opened not in other cases
611 */
612 if (copy_from_user(&metadata, (void __user *)arg, sizeof(metadata)))
613 return -EFAULT;
614
615 retval = stream->ops->set_metadata(stream, &metadata);
616 stream->metadata_set = true;
617
618 return retval;
619}
620
621static inline int
622snd_compr_tstamp(struct snd_compr_stream *stream, unsigned long arg)
623{
624 struct snd_compr_tstamp tstamp = {0};
625 int ret;
626
627 ret = snd_compr_update_tstamp(stream, &tstamp);
628 if (ret == 0)
629 ret = copy_to_user((struct snd_compr_tstamp __user *)arg,
630 &tstamp, sizeof(tstamp)) ? -EFAULT : 0;
631 return ret;
632}
633
634static int snd_compr_pause(struct snd_compr_stream *stream)
635{
636 int retval;
637
638 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
639 return -EPERM;
640 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_PUSH);
641 if (!retval)
642 stream->runtime->state = SNDRV_PCM_STATE_PAUSED;
643 return retval;
644}
645
646static int snd_compr_resume(struct snd_compr_stream *stream)
647{
648 int retval;
649
650 if (stream->runtime->state != SNDRV_PCM_STATE_PAUSED)
651 return -EPERM;
652 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_PAUSE_RELEASE);
653 if (!retval)
654 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
655 return retval;
656}
657
658static int snd_compr_start(struct snd_compr_stream *stream)
659{
660 int retval;
661
662 if (stream->runtime->state != SNDRV_PCM_STATE_PREPARED)
663 return -EPERM;
664 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_START);
665 if (!retval)
666 stream->runtime->state = SNDRV_PCM_STATE_RUNNING;
667 return retval;
668}
669
670static int snd_compr_stop(struct snd_compr_stream *stream)
671{
672 int retval;
673
674 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
675 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
676 return -EPERM;
677 retval = stream->ops->trigger(stream, SNDRV_PCM_TRIGGER_STOP);
678 if (!retval) {
679 snd_compr_drain_notify(stream);
680 stream->runtime->total_bytes_available = 0;
681 stream->runtime->total_bytes_transferred = 0;
682 }
683 return retval;
684}
685
686static int snd_compress_wait_for_drain(struct snd_compr_stream *stream)
687{
688 int ret;
689
690 /*
691 * We are called with lock held. So drop the lock while we wait for
692 * drain complete notfication from the driver
693 *
694 * It is expected that driver will notify the drain completion and then
695 * stream will be moved to SETUP state, even if draining resulted in an
696 * error. We can trigger next track after this.
697 */
698 stream->runtime->state = SNDRV_PCM_STATE_DRAINING;
699 mutex_unlock(&stream->device->lock);
700
701 /* we wait for drain to complete here, drain can return when
702 * interruption occurred, wait returned error or success.
703 * For the first two cases we don't do anything different here and
704 * return after waking up
705 */
706
707 ret = wait_event_interruptible(stream->runtime->sleep,
708 (stream->runtime->state != SNDRV_PCM_STATE_DRAINING));
709 if (ret == -ERESTARTSYS)
710 pr_debug("wait aborted by a signal");
711 else if (ret)
712 pr_debug("wait for drain failed with %d\n", ret);
713
714
715 wake_up(&stream->runtime->sleep);
716 mutex_lock(&stream->device->lock);
717
718 return ret;
719}
720
721static int snd_compr_drain(struct snd_compr_stream *stream)
722{
723 int retval;
724
725 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
726 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
727 return -EPERM;
728
729 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_DRAIN);
730 if (retval) {
731 pr_debug("SND_COMPR_TRIGGER_DRAIN failed %d\n", retval);
732 wake_up(&stream->runtime->sleep);
733 return retval;
734 }
735
736 return snd_compress_wait_for_drain(stream);
737}
738
739static int snd_compr_next_track(struct snd_compr_stream *stream)
740{
741 int retval;
742
743 /* only a running stream can transition to next track */
744 if (stream->runtime->state != SNDRV_PCM_STATE_RUNNING)
745 return -EPERM;
746
747 /* you can signal next track isf this is intended to be a gapless stream
748 * and current track metadata is set
749 */
750 if (stream->metadata_set == false)
751 return -EPERM;
752
753 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_NEXT_TRACK);
754 if (retval != 0)
755 return retval;
756 stream->metadata_set = false;
757 stream->next_track = true;
758 return 0;
759}
760
761static int snd_compr_partial_drain(struct snd_compr_stream *stream)
762{
763 int retval;
764 if (stream->runtime->state == SNDRV_PCM_STATE_PREPARED ||
765 stream->runtime->state == SNDRV_PCM_STATE_SETUP)
766 return -EPERM;
767 /* stream can be drained only when next track has been signalled */
768 if (stream->next_track == false)
769 return -EPERM;
770
771 retval = stream->ops->trigger(stream, SND_COMPR_TRIGGER_PARTIAL_DRAIN);
772 if (retval) {
773 pr_debug("Partial drain returned failure\n");
774 wake_up(&stream->runtime->sleep);
775 return retval;
776 }
777
778 stream->next_track = false;
779 return snd_compress_wait_for_drain(stream);
780}
781
782static long snd_compr_ioctl(struct file *f, unsigned int cmd, unsigned long arg)
783{
784 struct snd_compr_file *data = f->private_data;
785 struct snd_compr_stream *stream;
786 int retval = -ENOTTY;
787
788 if (snd_BUG_ON(!data))
789 return -EFAULT;
790 stream = &data->stream;
791 if (snd_BUG_ON(!stream))
792 return -EFAULT;
793 mutex_lock(&stream->device->lock);
794 switch (_IOC_NR(cmd)) {
795 case _IOC_NR(SNDRV_COMPRESS_IOCTL_VERSION):
796 retval = put_user(SNDRV_COMPRESS_VERSION,
797 (int __user *)arg) ? -EFAULT : 0;
798 break;
799 case _IOC_NR(SNDRV_COMPRESS_GET_CAPS):
800 retval = snd_compr_get_caps(stream, arg);
801 break;
802 case _IOC_NR(SNDRV_COMPRESS_GET_CODEC_CAPS):
803 retval = snd_compr_get_codec_caps(stream, arg);
804 break;
805 case _IOC_NR(SNDRV_COMPRESS_SET_PARAMS):
806 retval = snd_compr_set_params(stream, arg);
807 break;
808 case _IOC_NR(SNDRV_COMPRESS_GET_PARAMS):
809 retval = snd_compr_get_params(stream, arg);
810 break;
811 case _IOC_NR(SNDRV_COMPRESS_SET_METADATA):
812 retval = snd_compr_set_metadata(stream, arg);
813 break;
814 case _IOC_NR(SNDRV_COMPRESS_GET_METADATA):
815 retval = snd_compr_get_metadata(stream, arg);
816 break;
817 case _IOC_NR(SNDRV_COMPRESS_TSTAMP):
818 retval = snd_compr_tstamp(stream, arg);
819 break;
820 case _IOC_NR(SNDRV_COMPRESS_AVAIL):
821 retval = snd_compr_ioctl_avail(stream, arg);
822 break;
823 case _IOC_NR(SNDRV_COMPRESS_PAUSE):
824 retval = snd_compr_pause(stream);
825 break;
826 case _IOC_NR(SNDRV_COMPRESS_RESUME):
827 retval = snd_compr_resume(stream);
828 break;
829 case _IOC_NR(SNDRV_COMPRESS_START):
830 retval = snd_compr_start(stream);
831 break;
832 case _IOC_NR(SNDRV_COMPRESS_STOP):
833 retval = snd_compr_stop(stream);
834 break;
835 case _IOC_NR(SNDRV_COMPRESS_DRAIN):
836 retval = snd_compr_drain(stream);
837 break;
838 case _IOC_NR(SNDRV_COMPRESS_PARTIAL_DRAIN):
839 retval = snd_compr_partial_drain(stream);
840 break;
841 case _IOC_NR(SNDRV_COMPRESS_NEXT_TRACK):
842 retval = snd_compr_next_track(stream);
843 break;
844
845 }
846 mutex_unlock(&stream->device->lock);
847 return retval;
848}
849
850static const struct file_operations snd_compr_file_ops = {
851 .owner = THIS_MODULE,
852 .open = snd_compr_open,
853 .release = snd_compr_free,
854 .write = snd_compr_write,
855 .read = snd_compr_read,
856 .unlocked_ioctl = snd_compr_ioctl,
857 .mmap = snd_compr_mmap,
858 .poll = snd_compr_poll,
859};
860
861static int snd_compress_dev_register(struct snd_device *device)
862{
863 int ret = -EINVAL;
864 char str[16];
865 struct snd_compr *compr;
866
867 if (snd_BUG_ON(!device || !device->device_data))
868 return -EBADFD;
869 compr = device->device_data;
870
871 sprintf(str, "comprC%iD%i", compr->card->number, compr->device);
872 pr_debug("reg %s for device %s, direction %d\n", str, compr->name,
873 compr->direction);
874 /* register compressed device */
875 ret = snd_register_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
876 compr->device, &snd_compr_file_ops, compr, str);
877 if (ret < 0) {
878 pr_err("snd_register_device failed\n %d", ret);
879 return ret;
880 }
881 return ret;
882
883}
884
885static int snd_compress_dev_disconnect(struct snd_device *device)
886{
887 struct snd_compr *compr;
888
889 compr = device->device_data;
890 snd_unregister_device(SNDRV_DEVICE_TYPE_COMPRESS, compr->card,
891 compr->device);
892 return 0;
893}
894
895/*
896 * snd_compress_new: create new compress device
897 * @card: sound card pointer
898 * @device: device number
899 * @dirn: device direction, should be of type enum snd_compr_direction
900 * @compr: compress device pointer
901 */
902int snd_compress_new(struct snd_card *card, int device,
903 int dirn, struct snd_compr *compr)
904{
905 static struct snd_device_ops ops = {
906 .dev_free = NULL,
907 .dev_register = snd_compress_dev_register,
908 .dev_disconnect = snd_compress_dev_disconnect,
909 };
910
911 compr->card = card;
912 compr->device = device;
913 compr->direction = dirn;
914 return snd_device_new(card, SNDRV_DEV_COMPRESS, compr, &ops);
915}
916EXPORT_SYMBOL_GPL(snd_compress_new);
917
918static int snd_compress_add_device(struct snd_compr *device)
919{
920 int ret;
921
922 if (!device->card)
923 return -EINVAL;
924
925 /* register the card */
926 ret = snd_card_register(device->card);
927 if (ret)
928 goto out;
929 return 0;
930
931out:
932 pr_err("failed with %d\n", ret);
933 return ret;
934
935}
936
937static int snd_compress_remove_device(struct snd_compr *device)
938{
939 return snd_card_free(device->card);
940}
941
942/**
943 * snd_compress_register - register compressed device
944 *
945 * @device: compressed device to register
946 */
947int snd_compress_register(struct snd_compr *device)
948{
949 int retval;
950
951 if (device->name == NULL || device->dev == NULL || device->ops == NULL)
952 return -EINVAL;
953
954 pr_debug("Registering compressed device %s\n", device->name);
955 if (snd_BUG_ON(!device->ops->open))
956 return -EINVAL;
957 if (snd_BUG_ON(!device->ops->free))
958 return -EINVAL;
959 if (snd_BUG_ON(!device->ops->set_params))
960 return -EINVAL;
961 if (snd_BUG_ON(!device->ops->trigger))
962 return -EINVAL;
963
964 mutex_init(&device->lock);
965
966 /* register a compressed card */
967 mutex_lock(&device_mutex);
968 retval = snd_compress_add_device(device);
969 mutex_unlock(&device_mutex);
970 return retval;
971}
972EXPORT_SYMBOL_GPL(snd_compress_register);
973
974int snd_compress_deregister(struct snd_compr *device)
975{
976 pr_debug("Removing compressed device %s\n", device->name);
977 mutex_lock(&device_mutex);
978 snd_compress_remove_device(device);
979 mutex_unlock(&device_mutex);
980 return 0;
981}
982EXPORT_SYMBOL_GPL(snd_compress_deregister);
983
984static int __init snd_compress_init(void)
985{
986 return 0;
987}
988
989static void __exit snd_compress_exit(void)
990{
991}
992
993module_init(snd_compress_init);
994module_exit(snd_compress_exit);
995
996MODULE_DESCRIPTION("ALSA Compressed offload framework");
997MODULE_AUTHOR("Vinod Koul <vinod.koul@linux.intel.com>");
998MODULE_LICENSE("GPL v2");